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    <title>ShellCheck: SC2173 – SIGKILL/SIGSTOP can not be trapped.</title>
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    <h1>SC2173 – ShellCheck Wiki</h1>
    <a href="https://github.com/koalaman/shellcheck/wiki/SC2173">See this page on GitHub</a>
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    <h2 id="sigkillsigstop-can-not-be-trapped">SIGKILL/SIGSTOP can not be
trapped.</h2>
<h3 id="problematic-code">Problematic code:</h3>
<div class="sourceCode" id="cb1"><pre class="sourceCode sh"><code class="sourceCode bash"><span id="cb1-1"><a href="SC2173.html#cb1-1" aria-hidden="true" tabindex="-1"></a><span class="bu">trap</span> <span class="st">&#39;echo &quot;unkillable&quot;&#39;</span> KILL</span></code></pre></div>
<h3 id="correct-code">Correct code:</h3>
<p>Not applicable. This is not possible.</p>
<h3 id="rationale">Rationale:</h3>
<p>SIGKILL and SIGSTOP can not be caught/ignored (according to POSIX and
as implemented on platforms including Linux and FreeBSD). Trying to trap
this signal has undefined results.</p>
<h3 id="exceptions">Exceptions:</h3>
<p>None. If you come across one, please file an issue about it.</p>
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